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Its secondary objective is to seek to pay shareholders the highest rate of return consistent with safety and liquidity. Fees and Expenses <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.</span></div> Shareholder Fees (fees paid directly from your investment) 25 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0047 0 0.0000 0.0047 Example The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn a 5% return each year and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be: 48 151 264 592 Principal Investment Strategies <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Under normal circumstances, Capital Preservation invests exclusively in short-term money market securities issued by the U.S. Treasury that are guaranteed by the direct full faith and credit pledge of the U.S. government. The income from these securities is exempt from state income tax. Examples of U.S. Treasury securities in which the fund may invest include Treasury bills and notes, and Treasury floating-rate notes. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Because this fund is a government money market fund, both retail and institutional shareholders may invest in the fund. This fund does not have the ability to impose a liquidity fee on the sale of shares or temporarily suspend redemptions in response to decreases in liquidity.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund may purchase U.S. Treasury securities through buy/sell back transactions. The fund may commit up to 35% of its total assets to such transactions.</span></div> Under normal circumstances, Capital Preservation invests exclusively in short-term money market securities issued by the U.S. Treasury that are guaranteed by the direct full faith and credit pledge of the U.S. government. You could lose money by investing in the fund. An investment in the fund is not a bank account and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. Fund Performance <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The fund’s past performance is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.</span></div> The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The fund’s past performance is not necessarily an indication of how the fund will perform in the future. americancentury.com Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown. Calendar Year Total Returns <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Highest Performance Quarter (4Q 2023): 1.25%        Lowest Performance Quarter (1Q 2022): 0.00%</span></div><div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">As of June 30, 2026, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 1.62%.</span></div> Highest Performance Quarter 2023-12-31 0.0125 Lowest Performance Quarter 2022-03-31 0.0000 2026-06-30 Investor Class year-to-date return 0.0162 Average Annual Total ReturnsFor the calendar year ended December 31, 2025 Investor Class 0.0387 0.0289 0.0182 Ginnie Mae Fund Investment Objective <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Ginnie Mae seeks high current income while maintaining liquidity and safety of principal by investing primarily in GNMA certificates.</span></div> Fees and Expenses <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following table describes the fees and expenses you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. More information about these and other discounts is available from your financial professional and in </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Calculation of Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> on page 28 of the fund’s prospectus, </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Appendix A</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> of the fund’s prospectus and </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> in </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Appendix B</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> of the statement of additional information.</span></div> You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. 100000 Shareholder Fees (fees paid directly from your investment) 0 0 0.0450 0 0 0 0 0 0 0.0100 0 0 25 0 0 0 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0054 0.0044 0.0054 0.0054 0.0054 0.0034 0 0 0.0025 0.0100 0.0050 0 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0055 0.0045 0.0080 0.0155 0.0105 0.0035 Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase. Example The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn a 5% return each year and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be: 56 177 308 690 46 145 252 567 528 694 875 1396 158 490 845 1643 107 335 580 1282 36 113 197 444 Portfolio Turnover <div style="margin-bottom:9pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During the most recent fiscal year, the fund’s portfolio turnover rate was 138% of the average value of its portfolio.</span></div> 1.38 Principal Investment Strategies <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Under normal market conditions, the fund invests at least 80% of its net assets in securities issued by the Government National Mortgage Association (GNMA). GNMA certificates represent interests in pools of mortgage loans and in the cash flows from these loans. Unlike many other mortgage-backed securities, the timely payment of principal and interest on these certificates is guaranteed by GNMA. GNMA’s payment guarantee is stronger than most other government agencies’ because it is backed by the full faith and credit pledge of the U.S. government. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">In addition, the fund may buy other U.S. government debt securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, these agencies or instrumentalities are authorized to borrow from the U.S. Treasury to meet their obligations. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">To generate additional income, the fund may purchase securities, including mortgage dollar rolls, in advance through when-issued and forward commitment transactions. The fund may commit up to 35% of its total assets to such transactions.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts and swap agreements, or in mortgage- or asset-backed securities, provided that such investments are in keeping with the fund’s investment objective.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">When determining whether to sell a security, the portfolio managers consider, among other things, current and anticipated changes in interest rates, current valuation relative to alternatives in the market, general market conditions and any other factors deemed relevant by the portfolio managers.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.</span></div> Under normal market conditions, the fund invests at least 80% of its net assets in securities issued by the Government National Mortgage Association (GNMA). <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Interest Rate Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— Generally, when interest rates rise, the fund’s share value will decline. The opposite is true when interest rates decline. This risk is higher for the fund than for other funds that have shorter weighted average maturities, such as money market funds and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Prepayment and Extension Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds that have similar weighted average maturities. Conversely, an issuer may exercise its right to pay principal on an obligation held by the fund later than expected (extend the obligation) especially in periods of rising interest rates. These events may lengthen weighted average maturity and potentially reduce the value of these securities.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Derivatives Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks including liquidity, interest rate, market, credit and correlation risk. Derivatives used for hedging or risk management may not operate as intended, may expose the fund to other risks, and may be insufficient to protect the fund from the risks they were intended to hedge.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Market Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The value of the securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, war, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Redemption Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The fund may need to sell securities at times it would not otherwise do so in order to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs and/or have adverse tax consequences. Redemption activity can occur for many reasons, including shareholder reactions to market events or product changes. To the extent that a large shareholder (including the advisor, another account advised by the advisor, a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Principal Loss Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.</span> <div style="margin-bottom:6pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.</span></div> Fund Performance <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. GNMA Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.</span></div> The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. GNMA Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. americancentury.com Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown. Calendar Year Total Returns <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Highest Performance Quarter (4Q 2023): 7.53%        Lowest Performance Quarter (3Q 2022): -5.34% </span></div><div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">As of June 30, 2026, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 1.18%.</span></div> Highest Performance Quarter 2023-12-31 0.0753 Lowest Performance Quarter 2022-09-30 -0.0534 2026-06-30 Investor Class year-to-date return 0.0118 Average Annual Total ReturnsFor the calendar year ended December 31, 2025 Investor Class Return Before Taxes 0.0741 -0.0033 0.0107 Return After Taxes on Distributions 0.0572 -0.0154 -0.0006 Return After Taxes on Distributions and Sale of Fund Shares 0.0436 -0.0077 0.0033 I Class1 Return Before Taxes 0.0751 -0.0023 0.0117 A Class Return Before Taxes 0.0232 -0.0149 0.0036 C Class2 Return Before Taxes 0.0634 -0.0132 0.0021 R Class Return Before Taxes 0.0700 -0.0082 0.0057 R5 Class Return Before Taxes 0.0762 -0.0013 0.0127 Bloomberg U.S. Aggregate Bond Index     (reflects no deduction for fees, expenses or taxes) (reflects no deduction for fees, expenses or taxes) 0.0730 -0.0036 0.0201 Bloomberg U.S. GNMA Index    (reflects no deduction for fees, expenses or taxes) 0.0808 0.0023 0.0150 <div style="margin-bottom:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.</span></div> The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs. Government Bond Fund Investment Objective <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund seeks high current income.</span></div> Fees and Expenses <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following table describes the fees and expenses you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. More information about these and other discounts is available from your financial professional and in </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Calculation of Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> on page 28 of the fund’s prospectus, </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Appendix A</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> of the fund’s prospectus and </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> in </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Appendix B</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> of the statement of additional information.</span></div> You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. 100000 Shareholder Fees (fees paid directly from your investment) 0 0 0.0450 0 0 0 0 0 0 0.0100 0 0 25 0 0 0 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0046 0.0036 0.0046 0.0046 0.0046 0.0026 0 0 0.0025 0.0100 0.0050 0 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0047 0.0037 0.0072 0.0147 0.0097 0.0027 <span style="color:#000000;font-family:'Times New Roman',serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase.</span> Example The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn a 5% return each year and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be: 48 151 264 592 38 119 208 469 520 670 833 1305 150 466 803 1553 99 310 537 1190 28 87 152 344 Portfolio Turnover <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During the most recent fiscal year, the fund’s portfolio turnover rate was 218% of the average value of its portfolio.</span></div> 2.18 Principal Investment Strategies <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Under normal market conditions, the fund invests at least 80% of its net assets in U.S. government debt securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities, such as the Government National Mortgage Association (Ginnie Mae), are supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, these agencies or instrumentalities are authorized to borrow from the U.S. Treasury to meet their obligations. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">To generate additional income, the fund may purchase securities, including mortgage dollar rolls, in advance through when-issued and forward commitment transactions. The fund may commit up to 35% of its total assets to such transactions.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts and swap agreements, or in mortgage- or asset-backed securities, provided that such investments are in keeping with the fund’s investment objective. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">When determining whether to sell a security, the portfolio managers consider, among other things, current and anticipated changes in interest rates, current valuation relative to alternatives in the market, general market conditions and any other factors deemed relevant by the portfolio managers.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.</span></div> Under normal market conditions, the fund invests at least 80% of its net assets in U.S. government debt securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities. <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Interest Rate Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— Generally, when interest rates rise, the fund’s share value will decline. The opposite is true when interest rates decline. This risk is higher for the fund than for other funds that have shorter weighted average maturities, such as money market funds or short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Prepayment and Extension Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds that have similar weighted average maturities. Conversely, an issuer may exercise its right to pay principal on an obligation held by the fund later than expected (extend the obligation) especially in periods of rising interest rates. These events may lengthen weighted average maturity and potentially reduce the value of these securities.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Derivatives Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks including liquidity, interest rate, market, credit and correlation risk. Derivatives used for hedging or risk management may not operate as intended, may expose the fund to other risks, and may be insufficient to protect the fund from the risks they were intended to hedge.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Market Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The value of the securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, war, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Principal Loss Risk </span>— At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund. <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.</span></div> Fund Performance <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. Government/MBS Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.</span></div> The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. Government/MBS Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. americancentury.com Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown. Calendar Year Total Returns <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Highest Performance Quarter (4Q 2023): 6.70%        Lowest Performance Quarter (3Q 2022): -4.89%</span></div><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">As of June 30, 2026, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 0.43%.</span> Highest Performance Quarter 2023-12-31 0.0670 Lowest Performance Quarter 2022-09-30 -0.0489 2026-06-30 Investor Class year-to-date return 0.0043 Average Annual Total ReturnsFor the calendar year ended December 31, 2025 Investor Class Return Before Taxes 0.0724 -0.0076 0.0122 Return After Taxes on Distributions 0.0546 -0.0207 0.0008 Return After Taxes on Distributions and Sale of Fund Shares 0.0425 -0.0112 0.0045 I Class1 Return Before Taxes 0.0723 -0.0067 0.0131 A Class Return Before Taxes 0.0216 -0.0192 0.0051 C Class2 Return Before Taxes 0.0606 -0.0175 0.0038 R Class Return Before Taxes 0.0659 -0.0126 0.0072 R5 Class Return Before Taxes 0.0745 -0.0056 0.0143 Bloomberg U.S. Aggregate Bond Index     (reflects no deduction for fees, expenses or taxes) (reflects no deduction for fees, expenses or taxes) 0.0730 -0.0036 0.0201 Bloomberg U.S. Government/MBS Index      (reflects no deduction for fees, expenses or taxes) 0.0709 -0.0053 0.0146 <div style="margin-bottom:10pt;margin-top:7pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.</span></div> The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs. Short-Term Government Fund Investment Objective <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund seeks high current income while maintaining safety of principal.</span></div> Fees and Expenses <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following table describes the fees and expenses you may pay if you buy, hold and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. More information about these and other discounts is available from your financial professional and in </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Calculation of Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> on page 28 of the fund’s prospectus, </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Appendix A</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> of the fund’s prospectus and </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> in </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Appendix B</span> of the statement of additional information. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. 100000 Shareholder Fees (fees paid directly from your investment) 0 0 0.0225 0 0 0 0 0 0 0.0100 0 0 25 0 0 0 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0054 0.0044 0.0054 0.0054 0.0054 0.0034 0 0 0.0025 0.0100 0.0050 0 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0055 0.0045 0.0080 0.0155 0.0105 0.0035 <span style="color:#000000;font-family:'Times New Roman',serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Purchases of $500,000 or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase.</span> Example The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, that you earn a 5% return each year and that the fund’s operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be: 56 177 308 690 46 145 252 567 305 475 660 1193 158 490 845 1643 107 335 580 1282 36 113 197 444 Portfolio Turnover <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During the most recent fiscal year, the fund’s portfolio turnover rate was 210% of the average value of its portfolio.</span></div> 2.10 Principal Investment Strategies <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Under normal market conditions, the fund buys short-term debt securities and will invest at least 80% of its net assets in U.S. government securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities. In addition, the fund may invest a portion of its assets in investment-grade debt securities, including debt securities of U.S. companies, and non-U.S. government mortgage-backed, asset-backed and other fixed-income securities. Under normal market conditions, the portfolio managers maintain a weighted average maturity of three years or less.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities, such as the Government National Mortgage Association (Ginnie Mae), are supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, these agencies or instrumentalities are authorized to borrow from the U.S. Treasury to meet their obligations. In general, securities issued by non-U.S. government entities such as corporations are backed only by the credit of the issuer.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">To generate additional income, the fund may purchase securities, including mortgage dollar rolls, in advance through when-issued and forward commitment transactions. The fund may commit up to 35% of its total assets to such transactions.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund also may invest in derivative instruments such as options, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swap agreements), in mortgage- or asset-backed securities, or in pre-refunded municipal securities, provided that such investments are in keeping with the fund’s investment objective.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">When determining whether to sell a security, the portfolio managers consider, among other things, current and anticipated changes in interest rates, current valuation relative to alternatives in the market, general market conditions and any other factors deemed relevant by the portfolio managers.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund may engage in active and frequent trading of portfolio securities to achieve its principal investment strategies. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains.</span></div> Under normal market conditions, the fund buys short-term debt securities and will invest at least 80% of its net assets in U.S. government securities, including U.S. Treasury securities and other securities issued or guaranteed by the U.S. government and its agencies and instrumentalities. <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Interest Rate Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— Generally, when interest rates rise, the fund’s share value will decline. The opposite is true when interest rates decline. This risk is higher for the fund than for other funds that have shorter weighted average maturities, such as money market funds. A period of rising interest rates may negatively affect the fund’s performance.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Prepayment and Extension Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The fund may invest in debt securities backed by mortgages or other assets. If these underlying assets are prepaid, the fund may benefit less from declining interest rates than funds that have similar weighted average maturities. Conversely, an issuer may exercise its right to pay principal on an obligation held by the fund later than expected (extend the obligation) especially in periods of rising interest rates. These events may lengthen weighted average maturity and potentially reduce the value of these securities.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Derivatives Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional instruments. Derivatives are subject to a number of risks including liquidity, interest rate, market, credit and correlation risk. Derivatives used for hedging or risk management may not operate as intended, may expose the fund to other risks, and may be insufficient to protect the fund from the risks they were intended to hedge.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Market Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The value of the securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, war, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Principal Loss Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.</span> <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.</span></div> Fund Performance <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. 1-3 Year Government Bond Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.</span></div> The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. 1-3 Year Government Bond Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. americancentury.com Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown. Calendar Year Total Returns <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Highest Performance Quarter (3Q 2024): 2.92%        Lowest Performance Quarter (1Q 2022): -2.27%</span></div><div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">As of June 30, 2026, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 0.56%.</span></div> Highest Performance Quarter 2024-09-30 0.0292 Lowest Performance Quarter 2022-03-31 -0.0227 2026-06-30 Investor Class year-to-date return 0.0056 Average Annual Total ReturnsFor the calendar year ended December 31, 2025 Investor Class Return Before Taxes 0.0491 0.0157 0.0158 Return After Taxes on Distributions 0.0334 0.0041 0.0075 Return After Taxes on Distributions and Sale of Fund Shares 0.0289 0.0070 0.0085 I Class1 Return Before Taxes 0.0502 0.0165 0.0167 A Class Return Before Taxes 0.0230 0.0083 0.0110 C Class2 Return Before Taxes 0.0389 0.0054 0.0072 R Class Return Before Taxes 0.0440 0.0106 0.0107 R5 Class Return Before Taxes 0.0512 0.0177 0.0178 Bloomberg U.S. Aggregate Bond Index   (reflects no deduction for fees, expenses or taxes) (reflects no deduction for fees, expenses or taxes) 0.0730 -0.0036 0.0201 Bloomberg U.S. 1-3 Year Government Bond Index    (reflects no deduction for fees, expenses or taxes) 0.0517 0.0176 0.0184 <div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.</span></div> The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs. Inflation-Adjusted Bond Fund Investment Objective <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund seeks to provide total return and inflation protection consistent with investment in inflation-indexed securities.</span></div> Fees and Expenses <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following table describes the fees and expenses you may pay if you buy, hold, and sell shares of the fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below. You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. More information about these and other discounts is available from your financial professional and in </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Calculation of Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> on page 16 of the fund’s prospectus, </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Appendix A</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> of the fund’s prospectus and </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Sales Charges</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> in</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%"> Appendix B</span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%"> of the statement of additional information.</span></div> You may qualify for sales charge discounts if you and your family invest, or agree to invest in the future, at least $100,000 in American Century Investments funds. 100000 Shareholder Fees (fees paid directly from your investment) 0 0 0 0.0450 0 0 0 0 0 0 0 0 0 0.0100 0 0 0 0 25 0 0 0 0 0 0 0 0 Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment) 0.0046 0.0036 0.0026 0.0046 0.0046 0.0046 0.0026 0.0021 0.0021 0 0 0 0.0025 0.0100 0.0050 0 0 0 0.0005 0.0005 0.0005 0.0005 0.0005 0.0005 0.0005 0.0005 0.0005 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0004 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0001 0.0052 0.0042 0.0032 0.0077 0.0152 0.0102 0.0032 0.0027 0.0027 0 0 0 0 0 0 0 0 -0.0021 0.0052 0.0042 0.0032 0.0077 0.0152 0.0102 0.0032 0.0027 0.0006 Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase. Example The example below is intended to help you compare the costs of investing in the fund with the costs of investing in other mutual funds. The example assumes that you invest $10,000 in the fund for the time periods indicated and then redeem all of your shares at the end of those periods, and that you earn a 5% return each year. The example also assumes that the fund’s operating expenses remain the same, except that it reflects the rate and duration of any fee waivers noted in the table above. Although your actual costs may be higher or lower, based on these assumptions your costs would be: 53 167 291 653 43 135 236 530 33 103 180 406 525 685 859 1362 155 481 830 1609 104 325 564 1248 33 103 180 406 28 87 152 344 6 19 34 77 Portfolio Turnover <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund pays transaction costs, such as commissions, when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the example, affect the fund’s performance. During the most recent fiscal year, the fund’s portfolio turnover rate was 44% of the average value of its portfolio.</span></div> 0.44 Principal Investment Strategies <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Under normal market conditions, the fund invests at least 80% of its net assets in inflation-adjusted bonds. The advisor considers inflation-adjusted bonds to include inflation-indexed bonds, notes, commercial paper, short-term instruments and other debt securities issued by the U.S. Treasury, by other U.S. government agencies and instrumentalities, and by other, non-U.S. government entities such as corporations and foreign governments. Inflation-indexed securities are designed to protect the future purchasing power of the money invested in them; their principal value may be indexed for changes in inflation. In addition, the fund may invest a portion of its assets in traditional U.S. Treasury, U.S. government agency or other non-U.S. government securities that are not inflation-indexed.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Securities issued or guaranteed by the U.S. Treasury and certain U.S. government agencies or instrumentalities, such as the Government National Mortgage Association (Ginnie Mae), are supported by the full faith and credit of the U.S. government. Securities issued or guaranteed by other U.S. government agencies or instrumentalities, such as the Federal National Mortgage Association (Fannie Mae), the Federal Home Loan Mortgage Corporation (Freddie Mac), and the Federal Home Loan Bank are not guaranteed by the U.S. Treasury or supported by the full faith and credit of the U.S. government. However, these agencies or instrumentalities are authorized to borrow from the U.S. Treasury to meet their obligations. In general, securities issued by non-U.S. government entities are backed only by the credit of the issuer. </span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund invests primarily in investment-grade securities, but may also invest a portion of its assets in high-yield securities, or junk bonds. A high-yield security is one that has been rated below the four highest categories by a nationally recognized rating organization.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">There are no maturity or duration restrictions for the securities in which the fund may invest.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Although the fund invests primarily in U.S. dollar-denominated securities, the fund also may invest in securities denominated in foreign currencies.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">To generate additional income, the fund may purchase securities, including mortgage dollar rolls, in advance through when-issued and forward commitment transactions. The fund may commit up to 35% of its total assets to such transactions.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The fund also may invest in derivative instruments such as futures contracts and swap agreements (including, but not limited to, inflation swap agreements and credit default swap agreements), bank loans, securities backed by mortgages or other assets and collateralized obligations (including collateralized loan obligations). The fund may invest in U.S. Treasury futures, inflation swap agreements and credit default swap agreements to manage duration, inflation and credit exposure.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">When determining whether to sell a security, the portfolio managers consider, among other things, current and anticipated changes in interest rates, current valuation relative to alternatives in the market, general market conditions and any other factors deemed relevant by the portfolio managers.</span></div> Under normal market conditions, the fund invests at least 80% of its net assets in inflation-adjusted bonds. <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Inflation-Indexed Bonds Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— If the index measuring inflation falls, the principal value of inflation-indexed bonds will be adjusted downward, and consequently the interest payable on these securities will be reduced. In addition, interest payments on inflation-indexed bonds may be difficult to predict and may vary as the principal and/or interest is adjusted for inflation. In periods of deflation, the fund may have no income at all from such investments.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Interest Rate Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— Investments in debt securities are sensitive to interest rate changes. Generally, the value of debt securities and the funds that hold them decline as interest rates rise. The fund’s interest rate risk is generally higher than for funds with shorter-weighted average maturities, such as money market and short-term bond funds. A period of rising interest rates may negatively affect the fund’s performance.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Credit Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The value of the fund’s debt securities will be affected adversely by the inability or perceived inability of the issuers of these securities to make interest and principal payments as they become due. As a result, the fund’s share price could also decrease. Changes in the credit rating of a debt security held by the fund could have a similar effect.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">High-Yield Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— Issuers of high-yield securities, or junk bonds, are more vulnerable to real or perceived economic changes (such as an economic downturn or a prolonged period of rising interest rates), political changes or adverse developments specific to an issuer. These factors may be more likely to cause an issuer of low quality bonds to default on its obligations. High-yield securities (junk bonds) are also inherently speculative.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Liquidity Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— During periods of market turbulence or unusually low trading activity, in order to meet redemptions it may be necessary for the fund to sell securities at prices that could have an adverse effect on the fund’s share price. The market for lower-quality debt securities is generally less liquid than the market for higher-quality securities. Changing regulatory and market conditions, including increases in interest rates and credit spreads may adversely affect the liquidity of the fund’s investments.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Foreign Securities Risk </span>— Foreign securities have certain unique risks, such as currency risk, social, political and economic risk, and foreign market and trading risk. Securities of foreign issuers may be less liquid, more volatile and harder to value than U.S. securities. <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Bank Loan Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The market for bank loans may not be highly liquid and the fund may have difficulty selling them. Bank loans may not be considered securities, thus the fund may not be afforded anti-fraud protections available under the federal securities laws. In connection with purchasing loan participations, the fund generally will have no right to enforce compliance by borrowers with loan terms nor any set off rights, and the fund may not benefit directly from any posted collateral. As a result, the fund may be subject to the credit risk of both the borrower and the lender selling the participation. Bank loan transactions may take more than seven days to settle, meaning that proceeds would be unavailable to make additional investments or meet redemptions.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Collateralized Obligations Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— Collateralized obligations, such as collateralized loan obligations (CLOs) are subject to credit, interest rate, valuation, and prepayment and extension risks. These securities also are subject to risk of default on the underlying asset, particularly during periods of economic downturn. The market value of collateralized obligations may be affected by, among other things, changes in the market value of the underlying assets held by the collateralized obligation, changes in the distributions on the underlying assets, defaults and recoveries on the underlying assets, capital gains and losses on the underlying assets, prepayments on underlying assets and the availability, and prices and interest rate of underlying assets. Lower rated tranches of such debt are subject to a higher risk of total loss and deferral or nonpayment of interest than the more senior tranches to which they are subordinated. Some of the collateralized obligations in which the fund invests may be covenant-lite loans. Covenant-lite loans contain fewer or less restrictive constraints on the borrower. The fund may have fewer rights against a borrower and an accompanying greater risk of loss when it invests in covenant-lite loans.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Derivatives Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The use of derivative instruments involves risks different from the risks associated with investing directly in securities and other traditional instruments. The fund’s use of derivatives, and in particular its use of inflation swap agreements and credit default swap agreements, are subject to counterparty risk, which is the risk that the other party in the transaction will not fulfill its contractual obligation. Derivatives are also subject to a number of additional risks including liquidity, interest rate, market, credit and correlation risk. In addition, gains or losses involving some futures and other derivatives may be substantial - in part because a relatively small price movement in these securities may result in an immediate and substantial gain or loss for the fund. Derivatives used for hedging or risk management may not operate as intended, may expose the fund to other risks, and may be insufficient to protect the fund from the risks they were intended to hedge.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Market Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The value of the securities owned by the fund may go up and down, sometimes rapidly or unpredictably. Market risks, including political, regulatory, economic and social developments, can affect the value of the fund’s investments. Natural disasters, public health emergencies, war, terrorism and other unforeseeable events may lead to increased market volatility and may have adverse long-term effects on world economies and markets generally.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Redemption Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— The fund may need to sell securities at times it would not otherwise do so in order to meet shareholder redemption requests. Selling securities to meet such redemptions may cause the fund to experience a loss, increase the fund’s transaction costs and/or have adverse tax consequences. Redemption activity can occur for many reasons, including shareholder reactions to market events or product changes. To the extent that a large shareholder (including the advisor, another account advised by the advisor, a fund of funds or 529 college savings plan) invests in the fund, the fund may experience relatively large redemptions as such shareholder reallocates its assets.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">When-Issued and Forward Commitment Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— When-issued and forward commitments involve the risk that the security the fund buys will lose value prior to its delivery. There also is the risk that the security will not be issued or that the other party to the transaction will not meet its obligation. If this occurs, the fund may lose both the investment opportunity for the assets it set aside to pay for the security and any gain in the security’s price.</span> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Mortgage- and Asset-Backed Securities Risk </span>— Mortgage- and asset backed securities are subject to credit, interest rate, prepayment and extension risks. These securities also are subject to risk of default on the underlying mortgage or asset, particularly during periods of economic downturn. <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Mortgage Dollar Rolls Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— If the counterparty to whom the fund sells the security becomes insolvent, the fund’s right to repurchase the security may be restricted. Other risks involved in entering into mortgage dollar rolls include the risk that the value </span><div style="margin-bottom:3pt;margin-top:3pt;padding-left:18pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">of the security may change adversely over the term of the mortgage dollar roll and that the security the fund is required to repurchase may be worth less than the security that the fund originally held.</span></div> <span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%;padding-left:14.5pt">Principal Loss Risk </span><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">— At any given time your shares may be worth less than the price you paid for them. In other words, it is possible to lose money by investing in the fund.</span> <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">An investment in the fund is not a bank deposit, and it is not insured or guaranteed by the Federal Deposit Insurance Corporation (FDIC) or any other government agency.</span></div> Fund Performance <div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. For current performance information, including yields, please visit americancentury.com.</span></div><div style="margin-bottom:3pt;margin-top:3pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown.</span></div> The following bar chart and table provide some indication of the risks of investing in the fund. The bar chart shows changes in the fund’s performance from year to year for Investor Class shares. The table shows how the fund’s average annual returns for the periods shown compared with those of a broad measure of market performance. The table also shows returns for the Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index, which the advisor considers to be more representative of the fund's investment strategy. The fund’s past performance (before and after taxes) is not necessarily an indication of how the fund will perform in the future. americancentury.com Sales charges and account fees, if applicable, are not reflected in the bar chart. If those charges were included, returns would be less than those shown. Calendar Year Total Returns <div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">Highest Performance Quarter (2Q 2020): 4.91%        Lowest Performance Quarter (2Q 2022): -6.52% </span></div><div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:700;line-height:120%">As of June 30, 2026, the most recent calendar quarter end, the fund’s Investor Class year-to-date return was 1.23%.</span></div> Highest Performance Quarter 2020-06-30 0.0491 Lowest Performance Quarter 2022-06-30 -0.0652 2026-06-30 Investor Class year-to-date return 0.0123 Average Annual Total ReturnsFor the calendar year ended December 31, 2025 Investor Class Return Before Taxes 0.0667 0.0084 0.0270 1997-02-10 Return After Taxes on Distributions 0.0485 -0.0095 0.0133 1997-02-10 Return After Taxes on Distributions and Sale of Fund Shares 0.0394 -0.0012 0.0148 1997-02-10 I Class1 Return Before Taxes 0.0669 0.0095 0.0280 2017-04-10 Y Class1 Return Before Taxes 0.0680 0.0103 0.0290 2017-04-10 A Class Return Before Taxes 0.0154 -0.0033 0.0197 1998-06-15 C Class2 Return Before Taxes 0.0564 -0.0015 0.0182 2010-03-01 R Class Return Before Taxes 0.0612 0.0034 0.0218 2010-03-01 R5 Class Return Before Taxes 0.0690 0.0105 0.0291 2002-10-01 R6 Class Return Before Taxes 0.0696 0.0110 0.0273 2017-07-28 Average Annual Total ReturnsFor the calendar year ended December 31, 2025 G Class Return Before Taxes 0.0718 0.0131 0.0295 2017-07-28 Bloomberg U.S. Aggregate Bond Index    (reflects no deduction for fees, expenses or taxes) (reflects no deduction for fees, expenses or taxes) 0.0730 -0.0036 0.0201 Bloomberg U.S. Treasury Inflation Protected Securities (TIPS) Index    (reflects no deduction for fees, expenses or taxes) 0.0701 0.0112 0.0309 <div style="margin-bottom:3pt;margin-top:10pt"><span style="color:#000000;font-family:'Times New Roman',serif;font-size:10pt;font-weight:400;line-height:120%">The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs.</span></div> The after-tax returns are shown only for Investor Class shares. After-tax returns for other share classes will vary. After-tax returns are calculated using the historical highest individual federal marginal income tax rates and do not reflect the impact of state and local taxes. Actual after-tax returns depend on an investor’s tax situation and may differ from those shown. After-tax returns are not relevant to investors who hold their fund shares through tax-deferred arrangements, such as 401(k) plans or IRAs. Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase. Historical performance for the I Class prior to its inception (April 10, 2017) is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable. C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion. Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase. Historical performance for the I Class prior to its inception (April 10, 2017) is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable. C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion. Purchases of $500,000 or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase. Historical performance for the I Class prior to its inception (April 10, 2017) is based on the performance of R5 Class shares. I Class performance has been adjusted to reflect differences in expenses between classes, if applicable. C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion. Purchases of $1 million or more may be subject to a contingent deferred sales charge of 1.00% if the shares are redeemed within one year of the date of purchase. The advisor has agreed to waive the G Class’s management fee in its entirety. The advisor expects this waiver to remain in effect permanently and cannot terminate it without the approval of the Board of Trustees. Historical performance for the I and Y Classes prior to their inception is based on the performance of R5 Class shares. I and Y Class performance has been adjusted to reflect differences in expenses between classes, if applicable. C Class shares automatically convert to A Class shares after approximately eight years. All returns for periods greater than eight years reflect this conversion.